Can an ulcerated plaque progress to a penetrating ulcer?

Progression of Ulcerated Plaque to Penetrating Aortic Ulcer

Yes, an ulcerated plaque can progress to a penetrating atherosclerotic ulcer (PAU) when the ulceration extends through the internal elastic lamina into the media of the aortic wall. 1

Pathophysiology of Progression

• PAU is characterized by localized ulceration of an aortic atherosclerotic plaque that penetrates through the internal elastic lamina into the media, frequently associated with intramural hematoma (IMH) and diffuse atherosclerosis 1
• The progression occurs when an atherosclerotic plaque ulcerates and extends deeper through the arterial wall layers 2
• PAUs typically develop in segments of the aorta where atherosclerotic changes are most common, with over 90% of cases occurring in the descending thoracic aorta 2
• The classic appearance of a developed PAU is a mushroom-shaped protrusion of the aortic lumen with overhanging edges, similar to a gastric ulcer 3

Risk Factors for Progression

• Most patients with PAU are older males (typically >65 years), smokers, with multiple comorbidities including systemic hypertension, coronary artery disease, COPD, renal insufficiency, and concurrent abdominal aneurysm 1
• Uncontrolled hypertension is a significant risk factor for progression of ulcerated plaques to PAU and subsequent complications 2
• Symptomatic PAU disease is more likely to progress than asymptomatic disease (42.9% vs 16.7%) 4
• Diffuse atherosclerosis throughout the aorta increases the risk of plaque ulceration progressing to PAU 3

Complications of Progression

• When a PAU develops, especially when complicated with IMH, the risk of rupture can be as high as 33%-75%, and progression to dissection is associated with high mortality 1
• PAUs can lead to several serious complications:
  • Formation of intramural hematoma within the media 5
  • Development of saccular aneurysms (27.8% of cases) 4
  • Aortic rupture (4.1% of cases) 4
  • Progression to aortic dissection 6

Diagnostic Considerations

• Computed tomography (CT) is the diagnostic technique of choice for detecting PAU and monitoring progression 1, 2
• On CT, early PAU appears as ulceration of plaque, while advanced PAU shows as a mushroom-shaped protrusion with outward-facing edges 5
• Magnetic resonance imaging is superior to conventional CT in differentiating acute intramural hematoma from atherosclerotic plaque 7
• Transesophageal echocardiography can be useful for visualizing PAU progression, showing atherosclerotic plaques that protrude into the aortic lumen 7

Management Implications

• Symptom onset may indicate PAU expansion (tunica adventitia involvement); thus, urgent imaging and appropriate therapeutic intervention are needed to prevent aortic rupture 1
• Close follow-up imaging is indicated for ulcerated plaques and PAUs, particularly in symptomatic cases, which are more likely to require repair and undergo radiographic progression 4
• For uncomplicated type B PAU (descending aorta), initial medical therapy under careful surveillance is recommended 1
• High-risk imaging features that suggest progression and may warrant intervention include:
  • Maximum PAU width ≥13-20 mm 1
  • Maximum PAU depth ≥10 mm 1
  • Significant growth of PAU width or depth >5 mm/year 1
  • PAU associated with a saccular aneurysm 1
  • PAU with an increasing pleural effusion 1

Clinical Pitfalls to Avoid

• Asymptomatic PAUs are often diagnosed as incidental findings during imaging examinations, but should not be ignored as they can still progress to serious complications 1
• Conservative medical therapy for symptomatic patients with PAU may lead to recurrence of symptoms and eventual need for surgical intervention 3
• Differential diagnosis between PAU and other aortic ulcers is crucial as the risk of complications and management approaches differ 6
• Avoid delaying follow-up imaging, particularly during the first month after diagnosis, as this is when complications are most likely to develop 7